Method and system for linking printed objects with electronic content

ABSTRACT

The present invention relates to a method for linking printed objects to electronic content, comprising: a) providing at least one digital copy of a printed object to a server&#39;s database, wherein said digital copy represents at least portion of said printed object, wherein the content layout of both the digital copy and the printed object is the same; b) providing association of at least one section at the layout of said digital copy with an electronic content, either by extracting and saving the coordinates of each link in the digital copy or via an external list of links; c) processing said digital copy for distinguishing between two types of objects: text objects and non-text objects, wherein each text object represent at least portion of a word or a combination of at least two or more adjacent words in any orientation with respect to the plane of said printed object; d) coding each object from both types of objects according to its visual shape and its reference location with respect to a defined coordinates on the layout of said printed object, thereby representing said digital copy as an array of vectors in a binary format; e) creating clusters of similar binary vectors and assigning random array of characters to each of said clusters, and saving said array of characters as coded dictionary of “hashwords”, thereby converting said binary vectors into a searchable text form; f) capturing an image of at least portion of said printed object by a mobile device; g) processing said captured image for distinguishing between text objects and image oriented objects, and coding each of said objects according to its visual shape and its reference location with respect to the layout of said printed object, thereby representing said captured digital image as an array of vectors in a binary format; h) sending said array of binary vectors to said server via a communications network; i) converting each clustered vectors to a hashword; j) performing textual search for identifying the corresponding hashwords that essentially best match the hashwords that were coded from the digital copy , wherein the conversion of said array into hashwords is done either locally in the mobile device prior to the sending or remotely at said server after the sending; k) performing a geometrical matching among the best matches over the array of vectors that represent the captured image; l) calculating the location of the captured part on the best match digital copy and extracting the specific link aimed to by captured image; and m) sending the associated electronic content or a corresponding link of it from said server to said mobile device.

FIELD OF THE INVENTION

The present invention relates to the field of media services. More particularly, the invention relates to a method and system for providing an intuitive connection between printed media and digital media.

BACKGROUND OF THE INVENTION

Mobile device such as cellular phones are becoming increasingly popular in recent years. The newer generations of the mobile devices e.g., smart phones and tablets, offer enhanced camera specifications, high speed internet connection and a fast internal processor.

An example of a solution for linking between printed materials and electronic content is the use of barcodes. However, barcodes, such as QR code, suffers from major inherent problems as their size and look do not allow having many instances of it in a printed textual page, like hyperlinks commonly are. Having multiple number of barcodes in a page require unacceptable changes to the layout of the page.

It is the intention of this invention to use those enhanced functions to enable such advanced mobile devices become a mediator and a connector between the printed materials and electronic files via the internet.

It is an object of the present invention to offer users the comfort of printed media reading and the updatability and richness of the online media.

It is another object of the present invention to allow multiple “offline hyperlinks” in a printed media, without interfering with the look and feel of the printed object

Other objects and advantages of the invention will become apparent as the description proceeds.

SUMMARY OF THE INVENTION

The present invention relates to a method for linking printed objects to electronic content, comprising:

-   -   a) providing at least one digital copy of a printed object to a         server's database, wherein said digital copy represents at least         portion of said printed object, wherein the content layout of         both the digital copy and the printed object is the same;     -   b) providing association of at least one section at the layout         of said digital copy with an electronic content, either by         extracting and saving the coordinates of each link in the         digital copy or via an external list of links;     -   c) processing said digital copy for distinguishing between two         types of objects: text objects and non-text objects, wherein         each text object represent at least portion of a word or a         combination of at least two or more adjacent words in any         orientation with respect to the plane of said printed object;     -   d) coding each object from both types of objects according to         its visual shape and its reference location with respect to a         defined coordinates on the layout of said printed object,         thereby representing said digital copy as an array of vectors in         a binary format;     -   e) creating clusters of similar binary vectors and assigning         random array of characters to each of said clusters, and saving         said array of characters as coded dictionary of “hashwords”,         thereby converting said binary vectors into a searchable text         form;     -   f) capturing an image of at least portion of said printed object         by a mobile device;     -   g) processing said captured image for distinguishing between         text objects and image oriented objects, and coding each of said         objects according to its visual shape and its reference location         with respect to the layout of said printed object, thereby         representing said captured digital image as an array of vectors         in a binary format;     -   h) sending said array of binary vectors to said server via a         communications network;     -   i) converting each clustered vectors to a hashword;     -   j) performing textual search for identifying the corresponding         hashwords that essentially best match the haswords that were         coded from the digital copy , wherein the conversion of said         array into hashwords is done either locally in the mobile device         prior to the sending or remotely at said server after the         sending;     -   k) performing a geometrical matching among the best matches over         the array of vectors that represent the captured image;     -   l) Calculating the location of the captured part on the best         match digital copy and extracting the specific link aimed to by         captured image; and     -   m) sending the associated electronic content or a corresponding         link of it from said server to said mobile device.

According to an embodiment of the invention, the processing of the digital image comprising detecting the inter-line spacing and the inter-word spacing across the area of said digital image, and detecting the text and non-text areas in each line and determining word boundaries, thereby determining each text object and each non-text object.

According to an embodiment of the invention, the processing further comprises pre-processing the captured image by applying image processing algorithm(s) to a digital representation of said image. The pre-processing comprises performing different image manipulation and transformation corrections such as an image rotation for skew correction.

According to an embodiment of the invention, the method further comprises prior to the sending of the array of binary vectors, converting each vector from said array into a unique charters string (“hashwords”).

In another aspect the present invention relates to a system adapted to perform the method for linking printed objects to electronic content.

In another aspect the present invention relates to a computer program comprising computer program code means adapted to perform the method for linking printed objects to electronic content when said computer program is run on a computer based device, such as an MMD or a server.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a block diagram generally illustrating a system for linking printed object with electronic content, according to an embodiment of the invention;

FIG. 2 is a flow chart generally illustrating the descriptors extraction process, according to an embodiment of the invention ;

FIG. 3 is a flow chart generally illustrating the method of the invention; and

FIG. 4 generally illustrating an example of dividing an image into text and non-text segments, in order to apply different algorithm to each segment, according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Throughout this description the term “Mobile Media Device” or (MMD) is used to indicate a computer based device including but not limited to cellular phones, tablet computers, notebook computers and any other electronic device which includes a camera or other image capturing device.

Reference will now be made to several embodiments of the present invention, examples of which are illustrated in the accompanying figures. Wherever practicable similar or like reference numbers may be used in the figures and may indicate similar or like functionality. The figures depict embodiments of the present invention for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the invention described herein.

The system of the present invention enables users of an MMD to capture an image of a printed object (e.g., the object can be at least a portion of a printed article) and to get in return a corresponding electronic content (e.g., a video clip, picture, text, link to a web page and the like).

Examples of the invention provide an image processing method in which the captured image is converted into an array of clustered vectors (refer herein as descriptors) that is based on the inter-line spacing and inter-word spacing of text and non-text objects, at samples across the area of the image.

Aspects of the present invention and an exemplary computing operating environment will be described. FIG. 1 and the following discussion are intended to provide a brief, general description of a suitable computing environment in which the invention may be implemented. While the invention will be described in the general context of program modules that execute in conjunction with an application program that runs on an operating system on a MMD, those skilled in the art will recognize that the invention may also be implemented in combination with other program modules.

FIG. 1 schematically illustrates a system 10 for linking printed object with electronic content in accordance with an embodiment of the invention. The system comprises an MMD 150 and a server database 130. The MMD 150 is provided with a designated MMD application (e.g., a client) that is adapted to capture an image of a source object 100 in order to get in return an electronic content 120 (e.g. a video clip, picture, text, a link to a web page and the like) that is associated with the captured image of the source object 100. Source object 100 can be any printed material, such as a book, a magazine, a brochure, etc.

A digital copy 110 (e.g., a PDF file format) of the source object 100 with the same layout of the source object 100 is stored in the server 130. In other words, the source object 100 is the printed version of the stored digital copy 110. The digital copy 110 may include a single image or a plurality of images, wherein, for example, each image may represent at least one page (or sometimes only a portion of at least one page) of a printed article, such as a book or a magazine. The links of the relevant electronic content 120 to the source object 100 can be pre-defined in an association list 110A. The association list 110A contains the linked object (word, sentence, picture, etc.) and its coordinates in a page and the URL of the digital content; or can be embedded as a hyperlink within the digital copy 110 of source object 100.

For example, one or more hyperlinks can be embedded in the digital copy 110 (e.g., in form of a PDF format) as provided by the publisher 160 of the digital copy 110. According to this example, the publisher 160 may send/upload the digital copy 110 (e.g., image(s) of source pages and the association list 110A) or a PDF file of the final layout with embedded hyperlinks to the server 130.

The digital copy 110 and the association list 110A are processed to extract the relevant characteristics for the source object 100. The processing includes: a. the extraction of links/hyperlinks from a PDF file or saving the association list 110A with their coordinates as should virtually appear in the source object 100, and b. the conversion of the digital copy 110 into descriptors and then to text string (i.e., hashword). This enables saving a smaller size file and later a faster search and comparison process as will be described in further details hereinafter.

At the MMD side, after the user takes a photo of the printed source object 100 with the MMD 150, the designated MMD application processes the acquired image and sends data that represent the result of the processing to the server 130. The designated MMD application includes a coding algorithm 140A that converts the acquired image into a coded form (descriptor). According to an embodiment of the invention, the processing transforms the captured image into a coded image that is defined by a plurality of clustered vectors, wherein each vector represents information of a portion from the taken photo. The method/algorithm for generating the coded image will be explained in further details hereinafter and also with reference to FIGS. 2 and 3.

At the server side, the system 10 uses the coding algorithm 140A to convert the pages layout of the digital copy into descriptors and 140B (similar to the processing done to the source object 100 by MMD 150) and a searching algorithm 140B that identifies and matches between an existing image of the source object 100 (i.e., the digital copy 110) at the server's database 130 and the coded image sent from the MMD 150, which may contain only some similarities with the source object 100 (e.g., only portion of the image, distorted, poorly lit, not in focus, etc.).

An additional advantage provided by the invention is the link extraction from the digital copy 110, in which the system 10 extracts the location of every link in or associated with the digital copy 110 form of the source object 100 (e.g. the coordinates of every link in a page). Upon finding a match between the digital copy of the source object 100 and the data sent from the MMD 150, any hotspot (i.e., coordinates) appears in that data can be matched with the corresponding link, and the relevant electronic content or link(s) to it can then be send to the MMD 150. For example, the MMD 150 can be used to show/display the electronic content to the user.

According to an embodiment of the invention, system 10 is provided with web account capabilities, thereby allowing users to open a personal user web account 160. For example, a link to the electronic content is also saved in the personal user web account 160 for a later use (e.g., re-play, share, comment, etc.).

Turning now to the image coding algorithm, wherein according to the present invention the image processing of the digital image is used for distinguishing between two types of objects in the image: text objects and non-text objects (e.g. pictures). In general, the same processing applies both to the captured image by the MMD 150 and to the digital copy stored in the server 130. However, due to its nature (i.e., due to MMD's camera angle, light condition, distortions, etc.), a captured image usually requires some pre-processing tasks prior to the coding process, which the digital copy is usually not needed, such as the alignment of the captured image due to the MMD's camera angle.

For the sake of brevity, however, the process of image coding that was found to yield the best results and examples will be described hereinafter. Although of course less precise results can be obtained using alternative algorithms and, furthermore, algorithms comparable to one described herein can be employed, all of which is encompassed by the invention.

Processing of a captured image by the MMD 150 may involve the following steps:

-   -   Capturing an image of the source object 100 (e.g., a printed         article) by the designated application of MMD 150. The         designated may include a visual target frame (e.g., displayed on         the touchscreen of a smart-phone while aiming the camera to         capture an image) to help the user to take a photo of the region         of interest with respect to the entire layout of a page;     -   Processing the captured image, which may include common         pre-processing tasks such as greyscale conversion, alignment of         the image, etc. and the conversion of the captured image into a         vector representation by an array of descriptors (i.e., into a         coded image). The conversion includes the using of different         algorithms for extraction of text descriptors and non-text         descriptors from the captured image and the clustering of the         extracted descriptors; and     -   Sending the coded image to the server 130 for finding the         electronic content associated with the captured image.

At the server 130, the received descriptor clusters from MMD 150 are converted to hashwords, using the same methodology and dictionary as the conversion of descriptors of the digital copy. Then a search is conducted in order to find the correlated part in the digital copy that matches the acquired image sent from the MMD, and then find the electronic content associated with the captured image target. In general, the search procedure may involve the following steps:

-   -   Matching the hashwords of the captured image with the hashwords         of stored digital copies;     -   Finding link which coordinates matches the target frame as aimed         by the user with MMD's application;     -   Associating with relevant electronic content; and     -   Sending the electronic content or its link to the MMD 150. For         example, at the MMD 150 the user can play the electronic         content, share the electronic content, or store the electronic         content for later use.

According to some embodiments of the invention, the captured image coding process may involve the following steps, as generally shown in FIG. 2:

-   -   Capturing an image from a printed article (step 20);     -   Pre-processing the capturing image (step 21), which may include         common tasks such as greyscale conversion, alignment of the         image, etc.;     -   Applying segmentation process to separate text and non-text         elements in the image (step 22); and     -   Performing text and non-text descriptor extraction (steps 23 and         24) for converting each text object in the captured image into a         vector representation.

The descriptors extraction process may involve the following steps:

A. Descriptor Extraction—Text Descriptors

-   -   1. Converting the captured image to grey level, if required;     -   2. Applying a deskew algorithm to the captured image for         aligning horizontally text lines that appear in the captured         image. The algorithm can be any deskew algorithm or equivalent,         such as the public domain deskew algorithm provided by Leptonica         Image processing library;     -   3. Applying image binarization to the deskewed image (e.g., by         using the Sauvola method for local binarization);     -   4. Finding all blobs in the binarized image, wherein with         respect to text objects in the image the blobs may represent         words or part of words, and with respect to non-text objects the         blobs may represent portions of a figure or other image object.         Based on the inter-line and inter-word spacing in the captured         image, an array of blobs are derived which represents the visual         deployment of words in the captured image. The blobs may refer         to a sort of a bounding box that may include curved or         unsymmetrical outlines;     -   5. For each blob center, finding the distance in pixels to the         blob center that is closest to it;     -   6. Calculating the median of the founded distances;     -   7. Applying morphological operation by closing with rectangular         kernel of size f*median (e.g., f=2), wherein f is a tunable         parameter of the application. The term closing refers herein to         the operation of morphological noise removal, and as a result         the closing operation causes close enough blobs to be fused         together;     -   8. Finding again all blobs in the image after the closing         operation. If there is enough text in the image (e.g., even 3         lines of text will suffice) whole words will be in a single         blob;     -   9. Filtering small blobs and very large blobs, according to         tunable parameters of the algorithm;     -   10. Calculating bounding box for each blob to be used as a mask         between non-text objects (e.g., figures and images) and text         areas;     -   11. Taking the binary deskewed image (i.e., the binarized image)         and for each bounding box calculating the center of mass of the         “on” pixels that appear in it;     -   12. For each Bounding box: finding the average distance (in x         and y dimensions) of the “on” pixels in it from the calculated         center of mass (wherein x=fwidth and y=fheight). In binary         representation “1” refers to a black pixel (i.e., “on” pixel),         while “0” refers to a white pixels (i.e., no pixel)     -   13. For each Bounding Box: calculating a new Bounding box         centered in the calculated center of mass with width         f_(x)*fwidth and height f_(y)*fheight, wherein f_(x) and f_(y)         are tunable parameters of the algorithm;     -   14. Scaling bi-linearly each new Bounding Box to a fixed size         image with n_(y) row and n_(x) pixels in each row; wherein n_(x)         and n_(y) are tunable parameters of the algorithm; and     -   15. Flattening the scaled image to a vector row after row,         wherein said flattened scaled image refers herein to the text         descriptor.

B. Descriptor Extraction—Non-text Descriptors:

-   -   1. Resizing the Deskewed gray level image (as obtained in step         A.2 hereinabove) by a scale factor s*median (same as step see         A.7 hereinabove), wherein s is a tunable parameter of the         application;     -   2. Scaling the mask calculated in step A.10 hereinabove with         respect to the resized image and applying the scaled mask to the         resized image;     -   3. Extracting interest points by applying a corner detection         algorithm such as the AGAST Corner Detector, and if an interest         point falls inside the text area then discard it; and     -   4. For each valid feature point, extracting a binary descriptor         by applying a keypoint descriptor algorithm such as the FREAK:         FAST RETINA KEYPOINT algorithm, wherein this binary descriptor         represents the image (non-text) descriptor.

Only one example of each of the different types of image processing has been given. Those skilled in the art will be aware that many different image processing techniques are available for detecting patterns within images, and of course text is simply an image pattern. Thus, there are many different processes for detecting which parts of an image are text objects and which are non-text objects.

According to an embodiment of the invention, in order to provide a rapid search procedure for finding the matching between captured images and the stored digital copy of the source object, the descriptors in the systems' server 130 as extracted from the digital copies are converted into a hashwords (string text) form. The hashwords are saved in a coded dictionary and enables to search the database of server 130 in a text form (by utilizing common search engines such as Goggle's search engine, SQL, and the like). The dictionary building procedure may involve the following steps for each Text Descriptor and Non-text Descriptor:

-   -   1. given a database of images (e.g., as provided in PDF file         format of the digital copies), extracting all text descriptors         from all the digital copies; and     -   2. clustering all descriptors by applying cluster analysis such         as the hierarchical k-means algorithm for binary vectors;     -   3. assigning each cluster a random hashword (e.g., a 6-letter         word); and     -   4. repeating the same procedure of steps 1-3 for the Non-text         descriptors.

Referring now to FIG. 3, a flow chart generally illustrating an embodiment for implementing the method of the invention for linking printed object with electronic content is now described. This method of this embodiment involves the steps of:

-   -   acquiring an image by an MMD 150 (step 30);     -   performing descriptors extraction for text and non-text objects         within the acquired image (step 31) and sending the descriptors         from the MMD 150 to the system's server 130;     -   converting each of the received descriptors into text hashword         format using the aforementioned dictionary (step 32); the         descriptor to hashword conversion is described hereafter in         further details;     -   conducting a text search with the converted descriptors over         hashwords that appear in the dictionary (step 33). As         aforementioned hereinabove, the haswords appear in the         dictionary were extracted from digital copies (such as digital         copy 110) prior to the capturing of the image by the MMD 150         (such extraction process is generally indicated by numeral 131         in the figure);     -   Finding the best matches results for the conducted text search         (step 34);     -   For each one of the best matches, performing a geometrical         matching for providing a homograph score of best matches over         descriptors (step 35). The geometrical matching refers to the         task of matching the geometrical position of descriptors between         the descriptors that represent the acquired image and the         descriptors that represent each of the digital copies;     -   Selecting the best result according to the maximal matched         number of descriptors (i.e., the highest homograph score—as         described in further details hereinafter) between the acquired         image and the digital copy among the best matches (step 36); and     -   For the selected best result, locating the associated link or         electronic content (step 37) which was closest to the acquired         image center and sending it to the MMD 150 (step 38).

Descriptor To Hashword Conversion Procedure:

For given a descriptor and the dictionary building procedure as described hereinabove—creating clusters of similar descriptors and assigning random array of characters (e.g., letters) to the clusters. Those groups of characters will be saved as coded dictionary of “hashwords”.

Homography Scoring Of Database Results

Given a query image and its descriptors (i.e., as extracted from the acquired image—the source object) and probable target image (i.e., of a digital copy) and its descriptors, find the maximal number of descriptors that fit a homography between the two images using an algorithm known as RANSAC Homography fitting from the well-known public domain openCV library. Wherein, it is assumed that the document (i.e., the digital copy) with the highest rank is most probably the right one.

According to an embodiment of the invention, a source object is marked in a way that a user will know that this object is supported by the technology of the present invention, e.g., by adding a visual indicator to the source object.

According to an embodiment of the invention, MMD application may also be enabled to select a portion of text object or non-text object to which the image processing is to be applied. This can be done by displaying an aiming element while operating the MMD's application for capturing an image from a printed object. For example, the aiming element can be in form of the target frame as aforementioned hereinabove.

As will be appreciated by the skilled person the arrangement described in the figures results in a system that allows to link an object such as a printed page, sign, billboard, an exhibit in an exhibition or a landmark to electronic content (e.g., an ad, company website, sales representative, textual information, coupon, or any other kind of visual and/or audio content).

The system of the present invention enables to add multiple links in any printed article (e.g. a word, a sentence, a picture, an ad etc.), much like the functionality of hyperlinks in a web page without compromising the look and feel of the printed article. In addition, the system of the present invention provides the ability to link existing print (without adding markers for the reader). In that case the system can only identify a printed page. For example, if there are several links that are refer to the printed page, the system will display several buttons in the MMD's application for the reader to choose from. As a result, many already printed objects such as old books as well as new one are provided with functionality similar to the hyperlink. It allows using as many links as possible in a page, just like in an online page, but without compromising the look and feel.

An additional advantage provided by the invention is the ability of linking a video content (e.g. commercials ads on a TV) to an electronic content. Using the invention the user is able to use a cell phone application to take a picture/clip of the program played on the TV and get the electronic content to the cell phone (e.g. a coupon, web site, sale info, direct purchasing). For example, in such case, the system's server will store video clips, and the system will match the frame captured with a frame in the clip.

Although the method has been described above in connection with images captured by an MMD camera, however, the image processing can be applied to images which have been provided by other image capture devices.

The method described above can be implemented as a computer program to perform the image processing functions. Thus, an apparatus for implementing the invention can comprise a computer which processes a digital image file to perform the image analysis and subsequent correction. Generally, program modules include routines, programs, components, data structures, and other types of structures that perform particular tasks or implement particular abstract data types. The invention is also practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communication network. In a distributed computing environment, program modules may be located in both local and remote memory storage devices.

The functions described hereinabove may be performed by executable code and instructions stored in computer readable medium and running on one or more processor-based systems. However, state machines, and/or hardwired electronic circuits can also be utilized. Further, with respect to the example processes described herein, not all the process states need to be reached, nor do the states have to be performed in the illustrated order. Further, certain process states that are illustrated as being serially performed can be performed in parallel.

All the above will be better understood through the following illustrative and non-limitative examples. The example appearance and terminology as depicted and described herein, are intended to be illustrative and exemplary, and in no way limit the scope of the invention as claimed.

FIG. 4 shows an exemplary digital image of a source object that represents a printed layout of a page from a printed newspaper at different stages of processing, in accordance with an embodiment of the invention. The original digital image of the printed newspaper is indicated by numeral 41 (e.g., as acquired by an MMD). At the next processing stage, a binary representation of the digital image of the source object after applying the segmentation algorithm prior to extraction of text and non-text descriptors is shown (as indicated by numeral 42). At the next processing stage, each text object is represented by a bounding box form of at least portion of a printed word or a combination of at least two or more adjacent printed words in any orientation with respect to the plane of the printed layout (as indicated by numeral 43). At the next processing stage, the image is prepared for the extraction of the text and non-text descriptors, wherein numeral 44 indicates of the digital image that shows only the text objects, while numeral 45 indicates of the digital image that shows only the non-text objects. An example of the digital image of the source object after applying the segmentation algorithm and masking the text, preparing the non-text descriptors for extraction is indicated by numeral 45. An example of the digital image of the source object after applying the segmentation algorithm with the text objects, preparing the text descriptors for extraction is indicated by numeral 44.

In this embodiment, each text object is converted into an essentially quadrilateral form or bounding box, while words that contain letters that extend from the common virtual alignment line of each row results in corresponding higher from, such as the letters: b, d, f, g, h, k, l, p, q, t and y. Depending on the font attributes each different word (or portion of the word or combination of two or more words, depending on the line spacing, and inter-spacing between the words) may result in a unique form.

All the above description and examples have been given for the purpose of illustration and are not intended to limit the invention in any way. Many different mechanisms, methods of analysis, electronic and logical elements can be employed, all without exceeding the scope of the invention. 

1. A method for representing printed objects in searchable text form electronic content, comprising: a) providing a layout of a printed object; b) processing said layout for distinguishing objects including at least text objects, wherein each text object r represents a visual form of at least portion of a word or a combination of at least two or more adjacent words in any orientation with respect to said layout; c) coding each of said objects in a binary descriptor corresponding to its visual form in said layout; and representing said layout in a binary vector being an array of the binary descriptors of said objects arranged in accordance with locations of said objects in said layout; thereby enabling conversion of said binary vectors into a searchable text form based on hashwords assigned to said binary descriptors.
 2. The method according to claim 1, wherein the processing of the layout of the printed comprises detecting an inter-line spacing and an inter-word spacing across the layout, and determining word boundaries associated with the text objects.
 3. The method according to claim 1, further comprising pre-processing of an image indicative of the layout of the printed object, said pre-processing comprising: at least one of the following image processing algorithms applied to a digital representation of said image: an image rotation; skew correction; image binarization. 4-5. (canceled)
 6. A computer program product comprising a non-transitory computer readable medium having computer readable computer program code means adapted to perform the method of claim 1 when said computer program product is run on a computer based device.
 7. The method according to claim 1, wherein said providing of the layout associated with the printed object comprises receiving an image of at least portion of said printed object by a mobile device.
 8. The method according to claim 1, comprising sending data about said layout of the printed object to a server via a communications network, said data about the layout of the printed object being in the form of at least one of the following: the binary vector, and the searchable text form thereof.
 9. The method according to claim 1, comprising the conversion of the binary vector into the searchable text form thereof, said conversion comprising applying hashwords, assigned to the binary descriptors in the binary vector of the layout of the printed object, said conversion being carried out in a mobile device receiving an image of at least a portion of the printed object or at a server connected to the mobile device via a communication network.)
 10. The method according to claim 9, wherein the hashwords are respectively assigned to different clusters of the descriptors, each cluster corresponding to the same or similar descriptors.
 11. The method according to claim 1, further comprising providing data indicative of an electronic content of at least a portion of the printed object represented by the searchable text form, and sending said data to a mobile device, from which said at least portion of the printed object has been received in the form of the binary vector or the searchable text form thereof.
 12. The method according to claim 11, wherein said providing of the data indicative of the electronic content of the printed object represented by said searchable text form comprises utilizing a database which stores searchable text forms representing printed objects; and a database comprising a list of links associating sections of the layout of the printed object with corresponding electronic contents.
 13. The method according to claim 12, wherein said utilizing of the databases comprises: in response to received data about the layout of at least portion of the printed object, identifying the searchable text form thereof, performing textual search in the database of the searchable text forms to identify matching hashwords matching said searchable text form of the received data, determining the location of the portion of the printed object corresponding to said matching hashwords; performing a search in the list of links and identifying a section corresponding to said location and finding the corresponding electronic content.
 14. The method according to claim 13, wherein said determining the location comprises: performing a geometrical matching of the matching hashwords, determining a best match, and calculating the location of the best match in the layout.)
 15. The method according to claim 1, wherein the processing of the layout of the printed object comprises distinguishing between text and non-text objects in said layout.
 16. A server system connectable to mobile devices via a communication network, said server system being configured and operable for linking printed objects to electronic content, said linking comprising: providing searchable text forms of printed objects, each being created according to the method of claim 1 for the respective printed object; providing a list of links associating one or more sections of said print layout of the printed objects, which are represented by said searchable text forms, with respective electronic content; in response to data indicative of the layout of the printed object received from the mobile device via the network, identifying the searchable text form thereof; performing textual search in the database of the searchable text forms to identify matching hashwords matching said searchable text form of the received data, and determining the location of the portion of the printed object corresponding to said matching hashwords; performing a search in the list of links and identifying a section corresponding to said location and finding the corresponding electronic content; and sending said electronic content to the mobile device via the network.
 17. A mobile device connectable to a server via a communication network, the mobile device being configured and operable for carrying out the following: receiving image corresponding to at least a portion of a printed object; processing said image according to the method of claim 1 for providing data about the layout of said at least portion of the printed object being in the form of the binary vector or the searchable text form thereof, and sending said data about the layout of said at least portion of the printed object to the server via the communication network, thereby enabling receipt of an electronic content of said at least portion of the printed object from the server. 